public class Tractor {
    int load;
    int bulk;
    public Tractor(int load, int bulk){
        this.load=load;
        this.bulk=bulk;
        System.out.println("拖拉机载重："+load+",体积："+bulk);
    }
    public String qidon(){
        return  "启动";
    }
    public String shache(){
        return  "加速";
    }
}
